In the exploration of oil, gas and geothermal energy, drilling operations are used to create boreholes, or wells, in the earth. Conventional drilling involves having a drill bit on the bottom of the well. A bottom-hole assembly is located immediately above the drill bit where directional sensors and communications equipment, batteries, mud motors, and stabilizing equipment are provided to help guide the drill bit to the desired subterranean target.
A set of drill collars are located above the bottom-hole assembly to provide a non-collapsible source of weight to help the drill bit crush the formation. Heavy weight drill pipe is located immediately above the drill collars for safety. The remainder of the drill string is mostly drill pipe, designed to operate under tension. A conventional drill pipe section is about 30 feet long, but lengths vary based on style. It is common to store lengths of drill pipe in “doubles” (2 connected lengths) or “triples” (3 connected lengths). When the drill string (drill pipe, drill collars and other components) are removed from the wellbore to change-out the worn drill bit, the drill pipe and drill collars are set back in doubles or triples until the drill bit is retrieved and exchanged. This process of pulling everything out of the hole and running it all back in is known as “tripping.”
Tripping is non-drilling time and, therefore, an expense. Efforts have long been made to devise ways to avoid it or at least speed it up. Running triples is faster than running doubles because it reduces the number of threaded connections to be disconnected and then reconnected. Triples are longer and therefore more difficult to handle due to their length and weight and the natural waveforms that occur when moving them around. Manually handling moving pipe at the drill floor level can be dangerous.
It is desirable to have a drilling rig with the capability to reduce the trip time. One element of high speed trip rates that remains an obstacle is the handling of long lengths of thin tubulars assembled in stand lengths and, in particular, drill pipe. To maintain safety when accelerating trip rates, it is indicated to remove personnel from the drill floor and automate the handling of stand lengths of tubulars. The faster things happen around the wellbore, the more dangerous it is to have personnel on the drill floor. Additionally, faster movement of stand lengths of pipe creates greater harmonics in the stand, which are influenced by the increased acceleration. Accelerated movement of the lower end of a stand length also increases the momentum of the stand length, and the force that will be imparted when it impacts anything or anyone on the drill floor.
Therefore, it is desirable to have a drill floor mounted manipulating arm that is capable of stabilizing and guiding the lower end of a variety of drilling tubulars that are series connected in “stand” lengths of doubles, triples, or fourables. It is further desirable to have such a drill floor mounted manipulating arm that is capable of stabilizing and guiding the lower end of the tubulars to multiple locations proximate to the drill floor such that the guide can be used for multiple functions involving the tubulars.